Definition
A category or design of instrument used to measure temperature, classified by the physical principle it uses to sense and indicate temperature change. Common types in aviation include bimetallic strip thermometers, liquid-filled (capillary) thermometers, electrical resistance thermometers, and thermocouple thermometers.
Plain English
The kind of thermometer being used, named for how it actually senses temperature. Different aircraft systems use different kinds because each one works best for a particular job.
Context Anchor
Seen in aircraft maintenance manuals and instrument descriptions when identifying how an engine, oil, air, or component temperature is being measured.
Derivation
‘Type’ here simply means category or design. ‘Thermometer’ comes from the Greek therme (heat) and metron (measure) — literally a heat-measurer. So a ‘type thermometer’ is shorthand for ‘a thermometer of a particular design.’
Why Pilots Care
Correct temperature data supports performance calculations, engine monitoring, and icing avoidance.
Intuition Check
“Type” here does not mean aircraft model or aircraft category. It means the thermometer’s sensing method—how the instrument detects heat.
Example Sentence 1
The mechanic explained that the cylinder head temperature gauge uses a thermocouple type thermometer because it can handle high engine temperatures.
Example Sentence 2
Maintenance replaced the type thermometer in the oil system with a more accurate model.